In order to study the seismic response of the embankment slopes with different reinforcing measures, shaking table tests were performed on three embankment slope models (i.e., unreinforced embankment slope, 2-layer reinforced embankment slope and 4-layer reinforced embankment slope). Wenchuan earthquake motions and white noise excitations were performed to investigate the change of the model parameters, the horizontal acceleration response, the vertical acceleration response and the dynamic earth pressure response of embankment slopes. A comparison was made on the seismic response among the embankment slopes with different reinforcing measures. The results show that the natural frequency of reinforced embankment slope is larger than that of unreinforced embankment slope, and the reinforced embankment slope is less sensitive to seismic excitation. Horizontal acceleration response is obviously amplified by embankment slope. Horizontal acceleration magnification presents a decreasing trend with the increase of the peak value of input horizontal acceleration, and the decreasing ratio is higher for reinforced embankment slope. The vertical acceleration magnification of reinforced embankment slope is much smaller than that of unreinforced embankment slope, and the nonlinear characteristic of embankment slope in vertical direction is not as obvious as that in horizontal direction. Residual earth pressure is mainly induced at the upper part of embankment slope.

Transport and structural properties of metallic glass-forming liquid Cu50Zr50 are investigated by molecular dynamics simulation, under high pressures from 1 bar to 70 GPa. The following results have been obtained: (i) reversals of component diffusion coefficients (D Cu and D Zr) are observed at the reversion pressure. At low pressures below the reversion pressure, D Cu/D Zr decreases from about 1.4 to 1.0. At high pressures above the reversion pressure, D Cu/D Zr decreases more rapidly from 1.0 to about 0.7. (ii) Component diffusion coefficients decay exponentially with pressure up to reversion pressure, then the strength of the exponential dependence changes, while the pressure-dependent behavior of viscosity can be well described by a single exponential relation over the full range of pressure. (iii) The Stokes–Einstein relation (SER) works well at low pressures and starts to be violated at the breakdown pressure. For glass-forming liquid Cu50Zr50 along the 2000 K isotherm, the breakdown pressure equals the reversion pressure of component diffusion coefficients and is about 35 GPa. (iv) The pressure dependences of the ratio between component diffusion coefficients can be used to predict the breakdown pressure of SER along isotherm. The validity of SER and the reversals of component diffusion coefficients are found to be related to the pressure dependence of the relative total fractions of predominant Voronoi polyhedrons around individual components.

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We analyze the structure and rheological properties of ring and linear polymers under shear byusing the non-equilibrium molecular dynamics simulation. The simulation results show that compared with the ring chains, the linear polymers do not present prominent stress over shoot phenomenon. Since the overshoot reflects the maximum flow-induced deformation of the polymer, this qualitative observation already implies that the ring experience less deformation than its linear precursor in simple shear flow. This is consistent with the recent experimental result. In order to further study the molecular mechanism of this phenomenon, the segmental structure and orientation angle distribution as a function of strain under the different Weissenberg numbers are given in this study. The weak overshoot of the stretching of the ring polymers proves that the weak shear thinning and peak strain are due to the weak deformation of the segment chain of the ring in the shear flow. The rheological properties of linear and ring system are extracted from the stress-strain curves, can be used further to analyze the data. The peak strain <i>γ</i>_max as afunction of <i>Wi</i>_R follows a power-law with an exponent of 0.3 for linear polymer at <i>Wi</i>_R>1, however, for the ring system thepeak strain follows a power-law with an exponent of 0.1. The parameter <i>η</i>_max/<i>η</i>_steady is also the measure of the effective chain deformation at a steady state. The data show its progressive increase with <i>Wi</i>_R increasing, and follows a power-law with a scaling slop of 0.13 and 0.08 for linear and ring polymers, respectively. The peak stress <i>σ</i>_max as a function of <i>Wi</i>_R is also extracted from stress-strain curve. The two investigated systems both obey the scaling law with an exponent of 0.5. The normalized steady-state shear viscosity obeys a shear thinning slop of –0.86 for the linear polymer, the ring polymer obeysa shear thinning slop of –0.4. According to the gyration tensor and orientation angle, the power-law relationship between stretching and orientation is also given in this work.

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